Automatic brake for a shopping cart

ABSTRACT

For a shopping cart having a frame mounted on roll-about wheels, an automatic lock which is released by a timing mechanism a predetermined period of time after actuation. A photoelectric cell is operatively associated with the timing mechanism so that a beam of light, e.g., at a store exit can actuate the mechanism. A rechargeable battery is included and male and female electrical connectors are disposed in opposite forward and rearward directions on the cart for mating engagement with counterpart connectors on other like-constructed carts stacked therewith, whereby recharging of the batteries of each stacked cart can be simultaneously accomplished from a single source of electrical power.

United States Patent La Brie, Jr..'. ..280/33.99 C X Hlggs. ['45] Mar.28, 1972 [54] AUTOMATIC BRAKE FOR A SHOPPING 3,031,037 4/1962 Stollman..280/33.99 C ox CART 3,394,945 7/1968 Steier et al. ..280/33.99 C3,201,139 8/1965 Turlington ..280/33.99 C Inventor: Stuart gg 12533Emelita St, North 3,331,200 7/1967 Byron et al ..ss/39.5 x

Hollywood, Calif. 91607 Filed Mar 23 1970 FOREIGN PATENTS ORAPPLICATIONS 1 472,025 2/1929 Germany ......180/1 14 [211 Appl. No.:21,776

Primary Examiner-Benjamin Hersh Assistant Examiner-Milton L. Smith [52]Us. Cl. Att0rneyNilsson, Robbins, Wills& Berliner [51] Int. Cl .l ..B62b/04 ['58] Field ofSearch .....2s0/33.99; /268, 269, 267, [571, ABSTRACTI 70/226, 225, 271, 283; 340/280, 416, 224, 282; For a shopping carthaving a frame mounted on roll-about l/1 l4', l88/3l, 19,29, 163;58/395, 152 R, 152 wheels, an automatic lock which is released by atiming O mechanism a predetermined period oftime after actuation. Aphotoelectric cell is operatively associated with the timing [56]References Cited mechanism so that a beam of light, e.g., at a storeexit can actuate them echanism, A rechargeable battery is included andUNITED STATES PATENTS male and female electrical connectors are disposedin opposite forward and rearward directions on the cart for mating 8 23;engagement with counterpart connectors on other like-com 3 0 4/1962 o aC Ux structed carts stacked therewith, whereby recharging of thebatteries of each stacked cart can be simultaneously accom- )377065/l960 Chandler. /19 H pushed from a Single Source electrical power.2,964,140 12/1960 Berezny ..280/33.99 C X 8 Claims, 5 Drawing FiguresPATENTEDMAR28 I972 3,652,103

I NVE NTOR.

. 1 AUTOMATIC BRAKE FOR A SHOPPING CART FIELD or THE INVENTION Thefields of art to which the invention pertains include the fields ofautomatic vehicle trips, wheeled vehicles of the nesting type, andautomatic locking devices.

BACKGROUND AND SUMMARY or THE INVENTION,

In the modern supermarket and in other retail establishments, shoppingcarts are provided for use by the customers while selecting merchandiseand so that the customer can conveniently carry the merchandise past thecheckout counter and to his automobile, generally parked on an adjacentpark ing lot. However, a number of customers may live within walk ingdistance to the market and such customers may wheel the cart to theirhomes with the result that the carts are often not returned to themarket. In order to minimize or eliminate such losses, some markets haveresorted to the placement of bar-' ricades around the exit areas fromthe parking lot in the form of vertical posts having a spacing which isless than that of the shopping cart but which allows a customer tocarry. material through in his arms/Such barricades are generallyunsightly and have the effect of limiting open access to the parking lotwith resultant traffic, bottlenecks during peak shopping times. Otherdevices have been suggested which involve the use of locking mechanismsfor a wheel or axle of the shopping cart. For example, in US. Pat. Nos.2,964,l40, and 3,031,037, devices are disclosed which rely on magneticcomponents embedded in the concrete of the parking lotto trip a lockingmechanism. Such devices require a delicate balancing of components foreffective operation and do not respond uniformly at all speeds ofrotation. Other devices are exemplified by US. Pat; Nos. 3,002,370, and3,394,945, wherein a spring mechanism is wound tightly by movement ofthe cart'a predetermined distance so as to bind a wheelof the cart. withsuch mechanism, the cart becomes less free-rolling as one shopping cartwhich'allows the cart to be wheeledin ,freerolling fashion up until themoment of locking of the cart. is accomplished by providing a lockingmechanismwhich'is actuated only after a predetermined period of time haspassed after the customer leaves the store. This time period is determined as the period normally required for a customer to reach the mostdistant point in the markets parking lot'with addi" tional contingencytime for momentary delays.

The automatic lock comprises rotation-limiting means for at least one ofthe wheels of the cart, timing means operable when actuated to effectlocking of the rotationlimiting means after a predetermined period oftime, and means for actuating the-timing means. In a particularembodiment, a rigid locking bar is spring loaded in a releaseposition'adjacent a recess therefore in one of the cart wheels. Asolenoid is operatively associated with the locking bar to trip the barwhen actuated whereby to lock the wheel against forward and rearwardmovement. The solenoid is actuated by a timing mechanism which, in turn,is actuated by means of energization of a photoelectric cell carried onthe cart. A light source for the photoelectric cell is disposedexteriorly of the cart at an exit position in the door so that when thecart is pushed out of the exit, the timing mechanism is actuated tostart the predetermined period oftime.

In a further embodiment, a rechargeable battery source of power isprovided for operation of the lock. In this regard, the cart is formedto be stackable with other like-constructed carts and male and femaleconnectors are disposed on each cart in opposite forward and rearwarddirections for mating engagement with counterpart connectors on adjacentcarts.

By such means the batteries of each cart may be recharged simultaneouslyfrom a single source of electrical power.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a front-side perspective view of ashopping cart schematically showing component's constituting theautomatic lock of this invention;

FIG. 2 is a cross-sectional view taken substantially along the line 2-2of FIG. 1, in the direction of the arrows;

FIG. 3 is a vertical plan view of a wheel adapted for utilization with alock of this invention, taken on the line 3-3 of FIG. 2, in thedirection of the arrows;

FIG. 4 is a schematic representation of an electrical circuit which canbe utilized in operation of the presentinvention;

FIG. 5 is a schematic depiction of a plurality of stacked connectorswhich may be utilized in the present invention.

DETAILED DESCRIPTION As required, a detailed illustrative embodiment ofthe invention is disclosed herein. However, it isto be understood thatthis embodiment merely exemplifies'the invention which may take manydifferent forms that are radically different from the specificillustrative embodiment disclosed. Therefore, specific structural andfunctional details disclosed herein are not to be interpreted aslimiting, but merely as a basis for the claims which define the scope ofthe invention.

Referring to FIG. 1, a conventional shopping cart is illustrated whichhas been fitted with components constituting an automatic lock of thisinvention. The cart 10 includes a tubular metal frame 12 on which ismounted a large wire basket 14 carrying a'handle 12 rearwardly thereofin the usual fashion. Two pairs of wheels are attached to the lowerperiphery of the frame 12, a forwardpair of wheels 16 and 18 which areswiveledly mounted on the frame 12 and a rearward pair 20 and 22whichare fixed in stationary fashion to the frame 12 so that they cannotswivel.

The automatic lock of this invention is constituted by a number ofcomponents variously located on the cart frame 12, including a lockingbar mechanism enclosed within a housing 24,'a' timing mechanismindicated schematically at 26, a photoelectric cell indicatedschematically at 28, a battery power source indicated schematically at30, and male and I female electrical connectors 32 and 34 respectively,enclosed by'a'housing indicated by dashed lines 36. Each of theforegoing'components cooperate to accomplish automatic timed locking ofthe cart 10 as hereinafter detailed.

Initially, the cart'10 is free-wheeling in that each of the wheels 16,18, 20am 22 are independently rotatable without restriction. However,one of the wheels has associated therewith a locking mechanism whichwhen actuated prevents its rotation. This wheel is advantageously chosenas a rear wheel; such as the wheel designated by the numeral 20, so thatit is locked'against rotation during travel of the cart 10, the

cart is not caused to abruptly stop but is merely cause to pivot aboutthe wheel 20 by means of the swiveling front wheels and 18.

' Referring to FIG. 2, the manner of construction of the wheel and thelocking mechanism therefore is illustrated. The wheel 20 comprises a rim38 of molded rubber supported circumferentially about a hub 40 centrallyjournaled on a bearing 42 for effecting rotation of the wheel 20.Thebearing 42 is journaled between the arms 44 and 46 of a clevis whichis secured to the underside of a horizontal tubing member 50 of theframe 12 by'means of a headed bolt 52 and nut 54 as shown.

The clevis 48 is formed along an outer side with an L- shapedmemberconstituting the side and top walls 56 and 58 respectively of thelocking bar housing 24. Referring additionally back to FIG. 1, thehousing 24 also includes front and rear walls 60 and 62 respectively,the front wall 60 defining a horizontally elongate slot 64 (indicated bydashed lines in FIG. 2) for purposes hereinafter described.

Referring additionally to FIG. 3, the outer surface 66 of the wheel hub40 is dished out to define a curved, somewhat elongate pocket 68 havinglead-in edges 72 sharply defined therefrom. The outer clevis arm 44defines an opening 74 which is shaped and positioned so as to coincidewith the pocket 68 when the wheel 20 is rotated so that the pocket 68 isat its uppermost rotational position. A rigid lock bar 76 is providedwith a lead end 78 thereof slidably within the clevis arm opening 74 andthe other end secured by means of a spring 80 to the inner surface ofthe housing sidewall 56. The lock bar 76 defines a cylindrical pocket 82which is positioned through the surface of the lock bar 76 so that whenthe lock bar 76 is pushed rearwardly against the spring 80, the pocket82 coincides with the movable core 84 of a solenoid shown schematicallyat 86. The solenoid 86 is rigidly secured within the housing 24 by meansnot shown.

In accordance with the foregoing arrangement, the lock bar 76 is springloaded against the side housing wall 56 by movement rearwardly thereofuntil the solenoid core 84 engages the pocket 82. The solenoid core 84is spring loaded as indicated schematically at 88 so that uponencountering the pocket 82 the core seats itself in the pocket 82 luglatching the lock bar 76 in a spring loaded position. A lug 90 is formeddepending from the lock bar 76 to facilitate such spring loading. Thelug 90 is horizontally positioned on the lock bar 76 so that when thelock bar 76 is an extreme rightward position, there is a small spacedefined between the lug 90 and the outer clevis arm 44 (as illustratedby the dashed lines 90 prime showing the lug in its extreme rightwardposition). This spacing is sufficient to enable the insertion of a toolsuch as a thin rod between the leg 90 and outer clevis arm 44 tofacilitate spring loading of the lock bar 76. It is for this purposethat the front housing wall 60 defines the horizontally longate slot 64previously referred to. Thus, one can spring load the lock bar 76 byincision of an appropriate tool through the front housing wall slot 64.The tool may be appropriately keyed to an odd shaped slot 64 to preventunauthorized release.

Referring now to FIG. 4 in conjunction with FIG. 1, there isschematically illustrated an electrical circuit for the automaticoperation of the locking mechanism of this invention. For purposes ofexplanation, it is assumed that initially the locking bar 76 has beenspring loaded and secured in a latched position by means of inserting ofthe solenoid core 84 into the locking bar pocket 82, thus allowing thecart to be free wheeling. Upon leaving the premises, a beam of light ofappropriate intensity and/or wave length, as known to the art, isapplied to the photoelectric cell 28. This may be accomplished bylocating the beam of light at a proper elevational position on an exitdoor jam, or such a beam of light may be shined manually on theauto-electric cell 28 by an employee of the store at the checkout stand.The photoelectric cell 28 is electrically connected on one side bywiring through the tubular cart frame 12 to one terminal of the battery30, and on the other side to a latching relay 94 (not shown in FIG. 1)which, in turn, is connected to the opposite terminal of the battery 30.When actuated by the externally applied light beam, the'photoelectriccell 28 causes current to be applied through the relay 94 effectingclosure of a switch 96 to actuate the timing mechanism 26. The timingmechanism 26 is illustrated schematically and can be constructed inaccordance with any of the known prior electric timing mechanisms. Thetiming mechanism 26 is preset so that following a predetermined periodof time after actuation, an electrical circuit is closed for actuationof the solenoid 86. Actuation of the solenoid 86 effects a withdrawal ofthe solenoid core 84 from the lock bar pocket 82, thereby tripping thelock bar 76. The lock bar 76 is then projected by the force of thespring 80 through the clevis arm opening 86 and into the hub pocket 68to lock the wheel in place, thereby preventing further movement of thecart 10.

Referring particularly to FIG. 1, there is illustrated an antitiltmechanism to prevent the shopper from tilting the cart so as to removethe rear wheel 20 from contact with the ground. For this purpose, aU-shaped tubular member 98 is fixed to the frame 12 at a locationforward of and adjacent to the front wheels 16 and 18. The U-shapedmember include a central reach 100 which is horizontal and extendstransversely of the cart 10 and which is only slightly above groundlevel. The reach 100 is held in its position by a pair of dependent armsI02 and 104. Accordingly, if the cart 10 is tilted so that a shoppertries to roll it on its front two wheels 16 and 18, the reach 100 willcontact the ground and prevent the rolling of the cart in such tiltedposition. A similar device can be installed sideways of and adjacent tothe rear wheel 22 to prevent tiling in that direction, although thisfeature is not shown in the drawing. Such antitilt mechanisms do notconstitute novel parts of this invention but are described merely forpurposes of completion.

Referring again to FIG. 1 in conjunction with FIG. 4, there is providedon a forward turn of the tubular frame 12 a connector housing 36 whichencloses a male electrical connector 32 and a female electricalconnector 34. The male and female connectors are disposed on oppositerearward and forward directions, respectively, of the frame 12 andconstitute part of a mechanism for recharging the battery 30. Shoppingcart such as illustrated herein are typically constructed so as to nestone within another whereby storage of a line of such carts is readilyaccommodated. The connectors 32 and 34 are disposed so that whenlike-constructed carts are nested in front of and in back of theillustrated cart 10, counterpart connectors on such like-constructedcarts are pushed into mating engagement with the connectors 32 and 34.This is illustrated in FIG. 5 wherein the connectors 32 and 34, disposedon opposite sides of the tubular frame 12 are shown in matinglyengagement with counterpart connectors. Thus, the male connector 32 ofthe cart 10 is illustrated in engagement with a counterpart femaleconnector 34' of a cart nested rearwardly thereof. Similarly, the femaleconnector 34 of the cart 10 is shown matingly engaged with a maleconnector 32 of a part nested forwardly thereof.

The purpose of the foregoing arrangement is to enable the batteries 30of each of a plurality of nested carts to be recharged simultaneously.Referring now additionally back to FIG. 4, the male connector 32 isconnected to a source of alternating current, such as ordinary housecurrent which is fed into a charger 106 electrically connected toopposite terminals of the battery 30. The alternating current can beapplied to the male connector 32 directly or by means of its connectionwith a female counterpart connector such as 34' illustrated in FIG. 5.In this regard, the female connector 34 is electrically connected inparallel with the male connector 32 so that a counterpart male connector32" of forwardly nested cart can be plugged therein to receive chargingcurrent simultaneously with the male connector 32. By such means, thebatteries of each cart in a stacked nest of carts can be rechargedsimultaneously.

By means of the foregoing construction, shopping carts 10 are providedwhich can be free wheeled in the marketing area of the store and whichupon leaving the store are actuated so that after a predetermined periodof time, e.g., 5 minutes, one wheel of the cart is locked againstfurther rotation, thereby preventing removal of the cart from thevicinity of the shopping area. The locking bar 76 can thereafter bereset by an employee having an appropriate tool therefore, as describedhereinabove.

I claim:

1. An automatic brake for a shopping cart having a frame mounted onroll-about wheels, said brake comprising:

rotation-impeding means for at least one of said wheels allowing freerotation of said wheel when in a released position and impeding rotationthereof when in a brake position, said rotation-impeding meanscomprising a rigid member adjacent the side of said one wheel and springloaded in said release position, said rigid member being formed toengage said one wheel side when in a brake position, and a solenoidmechanically connected to said rigid member to retain said rigid memberin said release position and separable therefrom when actuated to permitsaid rigid-member to move under the force of said spring to said brakeposition;

timing means;

said solenoid being actuated by said timing means after a predeterminedperiod of time to separate from said rigid member whereby said rigidmember engages said one wheel to brake said cart; and

means for actuating said timing means.

2. An automatic brake for a shopping cart having a frame mounted onroll-about wheels, said brake comprising:

rotation-impeding means for at least one of said wheels allowing freerotation of said wheel in a released position and impeding rotationthereof when in a brake position; timing means;

means actuated by said timing means to actuate said rotation-impedingmeans to effect braking by said rotationimpeding means after apredetermined period of time; and

means for actuating said timing means comprising electrical circuitry, aphotoelectric cell responsive to a light beam of predetermined intensityand/or wave length, means actuated by said photoelectric cellto actuatesaid timing means, and a light source exteriorly of said cart forproviding said light beam.

3. The invention according to claim 1 in which said rotation-impedingmeans is formed to lock said wheel against forward rotation.

4. The invention according to claim 1 in which said timing meanscomprises an electrically driven timing mechanism, said cart carrying asource of power for said mechanism.

5. The invention according to claim 1 in which said means for actuatingsaid timing means comprises an electrically operable mechanism, saidcart carrying asource of power for said mechanism. I

6. The invention according to'claim 1 including a battery source ofpower and means for recharging said battery.

7. An automatic brake for a shopping cart having a frame mounted onroll-about wheels, said brake comprising:

rotation-impeding means for at least one of said wheels allowing freerotation of said wheel when in a released position and impeding rotationthereof when in a brake position;

timing means operable when actuated to effect locking of saidrotation-impeding means after a predetermined period of time;

means for actuating said timing means;

at least one of said means being an electrically actuated means;

a battery source of power for said electrically actuated means; and

means for recharging said battery;

said cart being formed to be stackable with other like-constructed cartsand said recharging means comprising male and female connectors disposedon said cart in opposite forward and rearward directions for matingengagement with counterpart connectors on other like-constructed cartsstacked therewith whereby the rechargeable batteries of said stackedcarts may be recharged simultaneously from a single source of electricalpower.

8. An automatic brake for a shopping cart having a frame mounted onroll-about .wheels, said brake comprising:

electrically actuated means for impeding rotation of at least one ofsaid wheels;

a battery source of power;

means for recharging said battery; and

means for electrically connecting said electrically actuated means tosaid battery to draw power therefrom;

said cart being formed to be stackable with other like-constructed cartsand said recharging means comprising male and female connectors disposedon said cart in opposite forward and rearward directions for matingengagement withcounterpart connectors on other like-constructed cartsstacked therewith whereby the rechargeable batteries of said stackedcarts may be recharged simultaneously from a single source of electricalpower.

1. An automatic brake for a shopping cart having a frame mounted onroll-about wheels, said brake comprising: rotation-impeding means for atleast one of said wheels allowing free rotation of said wheel when in areleased position and impeding rotation thereof when in a brakeposition, said rotation-impeding means comprising a rigid memberadjacent the side of said one wheel and spring loaded in said releaseposition, said rigid member being formed to engage said one wheel sidewhen in a brake position, and a solenoid mechanically connected to saidrigid member to retain said rigid member in said release position andseparable therefrom when actuated to permit said rigid member to moveunder the force of said spring to said brake position; timing means;said solenoid being actuated by said timing means after a predeterminedperiod of time to separate from said rigid member whereby said rigidmember engages said one wheel to brake said cart; and means foractuating said timing means.
 2. An automatic brake for a shopping carthaving a frame mounted on roll-about wheels, said brake comprising:rotation-impeding means for at least one of said wheels allowing freerotation of said wheel in a released position and impeding rotationthereof when in a brake position; timing means; means actuated by saidtiming means to actuate said rotation-impeding means to effect brakingby said rotation-impeding means after a predetermined period of time;and means for actuating said timing means comprising electricalcircuitry, a photoelectric cell responsive to a light beam ofpredetermined intensity and/or wave length, means actuated by saidphotoelectric cell to actuate said timing means, and a light sourceexteriorly of said cart for providing said light beam.
 3. The inventionaccording to claim 1 in which said rotation-impeding means is formed tolock said wheel against forward rotation.
 4. The invention according toclaim 1 in which said timing means comprises an electrically driventiming mechanism, said cart carrying a source of power for saidmechanism.
 5. The invention according to claim 1 in which said means foractuating said timing meaNs comprises an electrically operablemechanism, said cart carrying a source of power for said mechanism. 6.The invention according to claim 1 including a battery source of powerand means for recharging said battery.
 7. An automatic brake for ashopping cart having a frame mounted on roll-about wheels, said brakecomprising: rotation-impeding means for at least one of said wheelsallowing free rotation of said wheel when in a released position andimpeding rotation thereof when in a brake position; timing meansoperable when actuated to effect locking of said rotation-impeding meansafter a predetermined period of time; means for actuating said timingmeans; at least one of said means being an electrically actuated means;a battery source of power for said electrically actuated means; andmeans for recharging said battery; said cart being formed to bestackable with other like-constructed carts and said recharging meanscomprising male and female connectors disposed on said cart in oppositeforward and rearward directions for mating engagement with counterpartconnectors on other like-constructed carts stacked therewith whereby therechargeable batteries of said stacked carts may be rechargedsimultaneously from a single source of electrical power.
 8. An automaticbrake for a shopping cart having a frame mounted on roll-about wheels,said brake comprising: electrically actuated means for impeding rotationof at least one of said wheels; a battery source of power; means forrecharging said battery; and means for electrically connecting saidelectrically actuated means to said battery to draw power therefrom;said cart being formed to be stackable with other like-constructed cartsand said recharging means comprising male and female connectors disposedon said cart in opposite forward and rearward directions for matingengagement with counterpart connectors on other like-constructed cartsstacked therewith whereby the rechargeable batteries of said stackedcarts may be recharged simultaneously from a single source of electricalpower.